One solution is 10% acid and another is 22% acid. How many cubic centimeters of each should be mixed to obtain 100 cubic centimeters of a solution that is 12% acid?

The answer to this problem 10?

The answer is two numbers the quantities of each of the two solutions that go into the mixture, if you gave some idea of the work or thinking that went into your suggested answer it would be easier for us to spot what difficulties you are having with this problem.

Let the volume in cc of solution 1 be , and of solution 2 be . Then as we have 100cc of mixture:

.

cc of solution 1 contains cc of acid, cc of solution 2 contains cc of acid, so the cc of mixture contains , and this is 12% of cc so:

So you need to solve these equations for and to get the required answer.

CB

Last edited by mr fantastic; May 2nd 2009 at 04:01 AM.
Reason: No edit - just flagging this reply as having been moved from a thrread containing a duplicate question.